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Cleavage of the actin-capping protein alpha -adducin at Asp-Asp-Ser-Asp633-Ala by caspase-3 is preceded by its phosphorylation on serine 726 in cisplatin-induced apoptosis of renal epithelial cells.
- Source :
-
The Journal of biological chemistry [J Biol Chem] 2000 Aug 18; Vol. 275 (33), pp. 25805-13. - Publication Year :
- 2000
-
Abstract
- Decreased phosphorylation of focal adhesion kinase and paxillin is associated with loss of focal adhesions and stress fibers and precedes the onset of apoptosis (van de Water, B., Nagelkerke, J. F., and Stevens, J. L. (1999) J. Biol. Chem. 274, 13328-13337). The cortical actin cytoskeletal network is also lost during apoptosis, yet little is known about the temporal relationship between altered phosphorylation of proteins that are critical in the regulation of this network and their potential cleavage by caspases during apoptosis. Adducins are central in the cortical actin network organization. Cisplatin caused apoptosis of renal proximal tubular epithelial cells, which was associated with the cleavage of alpha-adducin into a 74-kDa fragment; this was blocked by a general caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (z-VAD-fmk). Hemagglutinin-tagged human alpha-adducin was cleaved into a similar 74-kDa fragment by caspase-3 in vitro but not by caspase-6 or -7. Asp-Arg-Val-Asp(29)-Glu, Asp-Ile-Val-Asp(208)-Arg, and Asp-Asp-Ser-Asp(633)-Ala were identified as the principal caspase-3 cleavage sites; Asp-Asp-Ser-Asp(633)-Ala was key in the formation of the 74-kDa fragment. Cisplatin also caused an increased phosphorylation of alpha-adducin and gamma-adducin in the MARCKS domain that preceded alpha-adducin cleavage and was associated with loss of adducins from adherens junctions; this was not affected by z-VAD-fmk. In conclusion, the data support a model in which increased phosphorylation of alpha-adducin due to cisplatin leads to dissociation from the cytoskeleton, a situation rendered irreversible by caspase-3-mediated cleavage of alpha-adducin at Asp-Asp-Ser-Asp(633)-Ala.
- Subjects :
- Actins metabolism
Amino Acid Chloromethyl Ketones metabolism
Animals
Antineoplastic Agents pharmacology
COS Cells
Carrier Proteins metabolism
Caspase 3
Cell Death
Cisplatin pharmacology
Cytoskeleton metabolism
Dose-Response Relationship, Drug
Epithelial Cells metabolism
Fluorescent Antibody Technique
Humans
Immunoblotting
L-Lactate Dehydrogenase metabolism
Microfilament Proteins metabolism
Phosphorylation
Plasmids metabolism
Protein Isoforms
Protein Kinase C chemistry
Protein Kinase C metabolism
Rats
Serine metabolism
Time Factors
Transfection
Apoptosis
Calmodulin-Binding Proteins metabolism
Caspases metabolism
Kidney metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9258
- Volume :
- 275
- Issue :
- 33
- Database :
- MEDLINE
- Journal :
- The Journal of biological chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 10823823
- Full Text :
- https://doi.org/10.1074/jbc.M001680200